Method of making chain-stitch seams



Jail. 15, 1929. 1,699,423

-w. B RASE METHOD OF MAKING CHAIN STITCH SEAMS Filed April 25, 1925 Patented Jan. 15, 1929..

UNITED STATES PATENT OFFICE.

WILHELM'BRASE, 0F BERLIN, GERMANY, ASSIGNOR 0F ONE-HALF T0 CLEMENS GBAAFF, OFIBERLIN, GERMANY.

METHOD OF MAKING CHATN-STITCH SEAMS.

Application filed April 25, 1925, Serial No. 25,919, and in Germany April 17, 1924.

My invention has for its object to perfect the invention described in my United States Patent application Ser. No; 717,651, and to provide a new method of making chain stitch seams.

My said United States Patent application describes a multiple needle lock-stitch sewing machine with a single shuttle thread having the needles arranged in the direction in which the sewing proceeds, the feed of the cloth being greater than the distance between the needles or greater than the sum of the distances in the case of more than two needles.

I have found, that the combination of the same arrangement, claimed in the said U. S. Patent application in connection with double lock-stitch sewing machines, with chain stitch sewing machines produces a machine of this kind showing unexpected advantages. Chain stitch sewing machines having two needles arranged in the direction in which the sewing proceeds are well known. But with these known machines the feed of work was done in such a manner, that with every stitch the first needle entered the stitch hole of the s'econd needle in order to connect together the meshes of the seam. It was impossible however to increase the output of these known chain stitch'sewing machines. Now if with chain stitch sewing machines having several needles arranged in the direction in which the sewing proceeds the feed of the cloth is according to my new method changed in such a manner, that it is greater than the sum of the distances between said needles or, in case of merely two needles, greater than the distance between said two needles, the output of machines of this kind is also multiplied correspondingly, but besides this the surprising advantage is obtained that the meshes of the threads are connected together in such a manner, that a ripping up of the seam produced is rendered very diflicult.

The'diagrammatic drawing aflixe'd to this specification and forming .partthereof shows in Fig. 1 a sample of a seam made with this machine and in accordance with my improved method, while in Fig. 2' a bottom view of -Fig. 1 is illustrated. 1

As can be plainly seen from the drawing the seam is formed by passing a plurality of loops, in the present case two, down through the material to be sewed, which loops are spaced from each other in the direction of sewing. The last loop in the direction of sewing is designated 1 and the first loop 2. The lower ends of the said loops are then caught and moved into vertical alignment as the material to be sewed is advanced. The material is advanced a distance greater than the sum of the distances between the loops, or in the present example, greater than the distance between the two loops. The amount of advance is preferably twice the sum of the distances between the loops, or twice the distance between the two loops in the present example. The ends of the vertically aligned loops are moved to a position in which the last loop 1 which'is next inserted through the material will pass through them. The next loops are then caught and vertically held by the rearmost loops 1 of the next stitch.

' What I claim as my invention and desire to secure by Letters Patent is The, method of sewing which consists in aligned and the cycle is repeated. It will thus be seen that the ends of the loops are passing a set of loops through the material to be sewed, the loops of said set being at adistance from one another in the direction of sewing, catching the loops of said set below the cloth and moving them into vertical alignment, passing a newv similar set of loops through the material to be sewed, the last loop of said new set in the direction of sewing being passed at a distance from the point at, which the last loop of the first'set of loops was passed greater than the distance between the points at which the first and last loop of said first set of loops were passed through the material, and fixing the previously aligned loops of the first set by passing through them the last loop of the said new set, and then repeating the cycle.

In testimony whereof I alfix my signature. 

